I am working on something related to texture analysis, the input is basically a string of digits. One of the things that such a analyzer should be able to do, is to recognize certain patterns, and process it.

A simplified example could be, if you see a pattern that could be split into two numbers, between which the second one doubles the first one, then their sum should replace the original pattern.

I used e1 and e2 to represent the two functions, which is, in my real work, much more complex. I made a general regexp as bellow. I want to know whether there is a better way, and whether anyone see any potential performance improvement: 

sub e1 {
    shift() *2;
}

sub e2 {
    shift() + shift();
}

$a = "12.2424.4812367";
$a =~ s/((?:\d+(?:\.\d+)?))((??{e1($+)}))/e2($1, $2)/ge;
print $a;

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In this case, the output should be: 36.72397. (36.72 is the sum of 12.24 and 24.48, 3 is the sum of 1 and 2, 9 is the sum of 3 and 6, 7 is a non-match)

In reply to Is this enough good, or can be improved? by pg

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